CTU size signaling

ABSTRACT

A method, computer program, and computer system is provided for coding video data. Video data having a coding tree unit size is received. The coding tree unit size associated with the video data is signaled by setting two or more flags. The video data is encoded/decoded based on the flags corresponding to the signaled coding tree unit size.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority based on U.S. Provisional ApplicationNo. 62/905,339 (filed Sep. 24, 2019), the entirety of which isincorporated herein.

FIELD

This disclosure relates generally to field of data processing, and moreparticularly to video encoding and decoding.

BACKGROUND

ITU-T VCEG (Q6/16) and ISO/IEC MPEG (JTC 1/SC 29/WG 11) published theH.265/HEVC (High Efficiency Video Coding) standard in 2013 (version 1)2014 (version 2) 2015 (version 3) and 2016 (version 4). In 2015, thesetwo standard organizations jointly formed the JVET (Joint VideoExploration Team) to explore the potential of developing the next videocoding standard beyond HEVC In October 2017, they issued the Joint Callfor Proposals on Video Compression with Capability beyond HEVC (CfP). ByFeb. 15, 2018, total 22 CfP responses on standard dynamic range (SDR),12 CfP responses on high dynamic range (HDR), and 12 CfP responses on360 video categories were submitted, respectively. In April 2018, allreceived CfP responses were evaluated in the 122 MPEG/10th JVET meeting.As a result of this meeting, JVET formally launched the standardizationprocess of next-generation video coding beyond HEVC. The new standardwas named Versatile Video Coding (VVC), and JVET was renamed as JointVideo Expert Team. The current version of VTM (VVC Test Model), i.e.,VTM 6.

SUMMARY

Embodiments relate to a method, system, and computer readable medium forcoding video data. According to one aspect, a method for coding videodata is provided. The method may include receiving video data having acoding tree unit size. The coding tree unit size associated with thevideo data is signaled by setting two or more flags. The video data isencoded/decoded based on the flags corresponding to the signaled codingtree unit size.

According to another aspect, a computer system for coding video data isprovided. The computer system may include one or more processors, one ormore computer-readable memories, one or more computer-readable tangiblestorage devices, and program instructions stored on at least one of theone or more storage devices for execution by at least one of the one ormore processors via at least one of the one or more memories, wherebythe computer system is capable of performing a method. The method mayinclude receiving video data having a coding tree unit size. The codingtree unit size associated with the video data is signaled by setting twoor more flags. The video data is encoded/decoded based on the flagscorresponding to the signaled coding tree unit size.

According to yet another aspect, a computer readable medium for codingvideo data is provided. The computer readable medium may include one ormore computer-readable storage devices and program instructions storedon at least one of the one or more tangible storage devices, the programinstructions executable by a processor. The program instructions areexecutable by a processor for performing a method that may accordinglyinclude receiving video data having a coding tree unit size. The codingtree unit size associated with the video data is signaled by setting twoor more flags. The video data is encoded/decoded based on the flagscorresponding to the signaled coding tree unit size.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects, features and advantages will become apparentfrom the following detailed description of illustrative embodiments,which is to be read in connection with the accompanying drawings. Thevarious features of the drawings are not to scale as the illustrationsare for clarity in facilitating the understanding of one skilled in theart in conjunction with the detailed description. In the drawings:

FIG. 1 illustrates a networked computer environment according to atleast one embodiment;

FIG. 2 is a diagram of a quad-tree/binary-tree (QTBT) block structure,according to at least one embodiment;

FIGS. 3A-3D are exemplary syntax elements, according to at least oneembodiment.

FIG. 4 is an operational flowchart illustrating the steps carried out bya program that codes video data, according to at least one embodiment;

FIG. 5 is a block diagram of internal and external components ofcomputers and servers depicted in FIG. 1 according to at least oneembodiment;

FIG. 6 is a block diagram of an illustrative cloud computing environmentincluding the computer system depicted in FIG. 1 , according to at leastone embodiment; and

FIG. 7 is a block diagram of functional layers of the illustrative cloudcomputing environment of FIG. 6 , according to at least one embodiment.

DETAILED DESCRIPTION

Detailed embodiments of the claimed structures and methods are disclosedherein; however, it can be understood that the disclosed embodiments aremerely illustrative of the claimed structures and methods that may beembodied in various forms. Those structures and methods may, however, beembodied in many different forms and should not be construed as limitedto the exemplary embodiments set forth herein. Rather, these exemplaryembodiments are provided so that this disclosure will be thorough andcomplete and will fully convey the scope to those skilled in the art. Inthe description, details of well-known features and techniques may beomitted to avoid unnecessarily obscuring the presented embodiments.

Embodiments relate generally to the field of data processing, and moreparticularly to video encoding and decoding. The following describedexemplary embodiments provide a system, method and computer program to,among other things, code video data using separate flags to replace thecoding tree unit size syntax. Therefore, some embodiments have thecapacity to improve the field of computing by allowing for less memoryuse by saving bits through signaling a coding tree unit size throughflags.

As previously described, ITU-T VCEG (Q6/16) and ISO/IEC MPEG (JTC 1/SC29/WG 11) published the H.265/HEVC (High Efficiency Video Coding)standard in 2013 (version 1) 2014 (version 2) 2015 (version 3) and 2016(version 4). In 2015, these two standard organizations jointly formedthe JVET (Joint Video Exploration Team) to explore the potential ofdeveloping the next video coding standard beyond HEVC In October 2017,they issued the Joint Call for Proposals on Video Compression withCapability beyond HEVC (CfP). By Feb. 15, 2018, total 22 CfP responseson standard dynamic range (SDR), 12 CfP responses on high dynamic range(HDR), and 12 CfP responses on 360 video categories were submitted,respectively. In April 2018, all received CfP responses were evaluatedin the 122 MPEG/10th JVET meeting. As a result of this meeting, JVETformally launched the standardization process of next-generation videocoding beyond HEVC. The new standard was named Versatile Video Coding(VVC), and JVET was renamed as Joint Video Expert Team. The currentversion of VTM (VVC Test Model), i.e., VTM 6.

In HEVC, a coding tree unit is split into coding units by using aquadtree structure denoted as coding tree to adapt to various localcharacteristics. The decision on whether to code a picture area usinginter-picture (temporal) or intra-picture (spatial) prediction is madeat the coding unit level. Each coding unit can be further split intoone, two or four prediction units according to the prediction unitsplitting type. Inside one prediction unit, the same prediction processis applied and the relevant information is transmitted to the decoder ona prediction unit basis. After obtaining the residual block by applyingthe prediction process based on the prediction unit splitting type, acoding unit can be partitioned into transform units according to anotherquadtree structure like the coding tree for the coding unit. One of keyfeatures of the HEVC structure is that it has the multiple partitionconceptions including coding unit, prediction unit, and transform unit.However, using fixed length coding u(2) to describe the syntax log2_ctu_size_minus5 could waste one bit because there may only be threenumbers to be encoded: 0, 1, and 2 respectively, u(2) could waste onebit if the encoded number is 0 or 1. It may be advantageous, therefore,to replace the original coding tree unit size syntax with separate flagsin order to save bits in sequence parameter set.

Aspects are described herein with reference to flowchart illustrationsand/or block diagrams of methods, apparatus (systems), and computerreadable media according to the various embodiments. It will beunderstood that each block of the flowchart illustrations and/or blockdiagrams, and combinations of blocks in the flowchart illustrationsand/or block diagrams, can be implemented by computer readable programinstructions.

Referring now to FIG. 1 , a functional block diagram of a networkedcomputer environment illustrating a video coding system 100 (hereinafter“system”) for coding video data using separate flags to replace thecoding tree unit size syntax. It should be appreciated that FIG. 1provides only an illustration of one implementation and does not implyany limitations with regard to the environments in which differentembodiments may be implemented. Many modifications to the depictedenvironments may be made based on design and implementationrequirements.

The system 100 may include a computer 102 and a server computer 114. Thecomputer 102 may communicate with the server computer 114 via acommunication network 110 (hereinafter “network”). The computer 102 mayinclude a processor 104 and a software program 108 that is stored on adata storage device 106 and is enabled to interface with a user andcommunicate with the server computer 114. As will be discussed belowwith reference to FIG. 5 the computer 102 may include internalcomponents 800A and external components 900A, respectively, and theserver computer 114 may include internal components 800B and externalcomponents 900B, respectively. The computer 102 may be, for example, amobile device, a telephone, a personal digital assistant, a netbook, alaptop computer, a tablet computer, a desktop computer, or any type ofcomputing devices capable of running a program, accessing a network, andaccessing a database.

The server computer 114 may also operate in a cloud computing servicemodel, such as Software as a Service (SaaS), Platform as a Service(PaaS), or Infrastructure as a Service (IaaS), as discussed below withrespect to FIGS. 6 and 7 . The server computer 114 may also be locatedin a cloud computing deployment model, such as a private cloud,community cloud, public cloud, or hybrid cloud.

The server computer 114, which may be used for coding video data isenabled to run a Video Coding Program 116 (hereinafter “program”) thatmay interact with a database 112. The Video Coding Program method isexplained in more detail below with respect to FIG. 4 . In oneembodiment, the computer 102 may operate as an input device including auser interface while the program 116 may run primarily on servercomputer 114. In an alternative embodiment, the program 116 may runprimarily on one or more computers 102 while the server computer 114 maybe used for processing and storage of data used by the program 116. Itshould be noted that the program 116 may be a standalone program or maybe integrated into a larger video coding program.

It should be noted, however, that processing for the program 116 may, insome instances be shared amongst the computers 102 and the servercomputers 114 in any ratio. In another embodiment, the program 116 mayoperate on more than one computer, server computer, or some combinationof computers and server computers, for example, a plurality of computers102 communicating across the network 110 with a single server computer114. In another embodiment, for example, the program 116 may operate ona plurality of server computers 114 communicating across the network 110with a plurality of client computers. Alternatively, the program mayoperate on a network server communicating across the network with aserver and a plurality of client computers.

The network 110 may include wired connections, wireless connections,fiber optic connections, or some combination thereof. In general, thenetwork 110 can be any combination of connections and protocols thatwill support communications between the computer 102 and the servercomputer 114. The network 110 may include various types of networks,such as, for example, a local area network (LAN), a wide area network(WAN) such as the Internet, a telecommunication network such as thePublic Switched Telephone Network (PSTN), a wireless network, a publicswitched network, a satellite network, a cellular network (e.g., a fifthgeneration (5G) network, a long-term evolution (LTE) network, a thirdgeneration (3G) network, a code division multiple access (CDMA) network,etc.), a public land mobile network (PLMN), a metropolitan area network(MAN), a private network, an ad hoc network, an intranet, a fiberoptic-based network, or the like, and/or a combination of these or othertypes of networks.

The number and arrangement of devices and networks shown in FIG. 1 areprovided as an example. In practice, there may be additional devicesand/or networks, fewer devices and/or networks, different devices and/ornetworks, or differently arranged devices and/or networks than thoseshown in FIG. 1 . Furthermore, two or more devices shown in FIG. 1 maybe implemented within a single device, or a single device shown in FIG.1 may be implemented as multiple, distributed devices. Additionally, oralternatively, a set of devices (e.g., one or more devices) of system100 may perform one or more functions described as being performed byanother set .of devices of system 100.

Referring now to FIG. 2 , an exemplary QTBT block structure 200 isdepicted. The QTBT block structure 200 may include block partitioning byusing QTBT. An corresponding tree representation may also be depicted.The solid lines may indicate quadtree splitting and the dotted lines mayindicate binary tree splitting. In each splitting (i.e., non-leaf) nodeof the binary tree, one flag may be signalled to indicate whichsplitting type (i.e., horizontal or vertical) may be used, where 0 mayindicate horizontal splitting and 1 may indicate vertical splitting. Forthe quadtree splitting, there may be no need to indicate the splittingtype since quadtree splitting always splits a block both horizontallyand vertically to produce 4 sub-blocks with an equal size.

QTBT may remove the concepts of multiple partition types. For example,QTBT may remove the separation of the coding unit, prediction unit, andtransform unit concepts, and supports more flexibility for coding unitpartition shapes. In the QTBT block structure 200, a coding unit canhave either a square or rectangular shape. A coding tree unit (CTU) maybe partitioned by a quadtree structure. The quadtree leaf nodes may befurther partitioned by a binary tree structure. There may be twosplitting types in the binary tree splitting: symmetric horizontalsplitting and symmetric vertical splitting.

The binary tree leaf nodes may be called coding units (CUs), and thatsegmentation may be used for prediction and transform processing withoutany further partitioning. This means that the coding unit, predictionunit, and transform unit may have the same block size in the QTBT codingblock structure 200. A coding unit may include coding blocks (CBs) ofdifferent colour components (e.g. one coding unit may contain one lumaCB and two chroma CBs in the case of P and B slices of the 4:2:0 chromaformat) or may include a CB of a single component (e.g., one coding unitmay contain one either luma CB or two chroma CBs in the case of Islices).

The following parameters may be defined for the QTBT partitioningscheme:

coding tree unit size may be the root node size of a quadtree, the sameconcept as in HEVC;

MinQTSize may be the minimum allowed quadtree leaf node size;

MaxBTSize may be the maximum allowed binary tree root node size;

MaxBTDepth may be the maximum allowed binary tree depth; and

MinBTSize may be the minimum allowed binary tree leaf node size

In one example of the QTBT partitioning structure 200, the coding treeunit size may be set as 128×128 luma samples with two corresponding64×64 blocks of chroma samples. The MinQTSize may be set as 16×16. TheMaxBTSize may be set as 64×64. The MinBTSize (for both width and height)may be set as 4×4. The MaxBTDepth may be set as 4. The quadtreepartitioning may be applied to the coding tree unit first to generatequadtree leaf nodes. The quadtree leaf nodes may have a size from 16×16(i.e., the MinQTSize) to 128×128 (i.e., the coding tree unit size). Ifthe leaf quadtree node may be 128×128, it may not be further split bythe binary tree since the size may exceed the MaxBTSize (i.e., 64×64).Otherwise, the leaf quadtree node may be further partitioned by thebinary tree. Therefore, the quadtree leaf node may be also the root nodefor the binary tree and it has the binary tree depth as 0.

When the binary tree depth reaches MaxBTDepth (i.e., 4), no furthersplitting may be considered. When the binary tree node has width equalto MinBTSize (i.e., 4), no further horizontal splitting may beconsidered. Similarly, when the binary tree node has height equal toMinBTSize, no further vertical splitting may be considered. The leafnodes of the binary tree are further processed by prediction andtransform processing without any further partitioning. In one example,the maximum coding tree unit size may be 256×256 luma samples.

In addition, the QTBT scheme may support the flexibility for the lumaand chroma to have a separate QTBT structure. Currently, for P and Bslices, the luma and chroma CTBs in one coding tree unit may share thesame QTBT structure. However, for I slices, the luma CTB may bepartitioned into CUs by a QTBT structure, and the chroma CTBs may bepartitioned into chroma coding units by another QTBT structure. Thismeans that a CU in an I slice may include a coding block of the lumacomponent or coding blocks of two chroma components, and a coding unitin a P or B slice consists of coding blocks of all three colourcomponents.

Referring now to FIGS. 3A-3D, exemplary syntax elements 300A-300D aredepicted. Syntax elements 300A-300D may be used to signal the codingtree unit size in order to save bits.

According to one or more embodiments, two out of three flags may be usedto signal coding tree unit size, namely use_32_ctu_size_flag,use_64_ctu_size_flag, and use_128_ctu_size_flag. In one embodiment,use_32_ctu_size_flag may be signaled first. If use_32_ctu_size_flag maybe equal to 1, coding tree unit size signaling may be finished.Otherwise, use_64_ctu_size_flag may be signaled. In one embodiment,use_64_ctu_size_flag may be signaled first. If use_64_ctu_size_flag maybe equal to 1, coding tree unit size signaling may be finished.Otherwise, use_32_ctu_size_flag may be signaled. In one embodiment,use_32_ctu_size_flag may be signaled first. If use_32_ctu_size_flag maybe equal to 1, coding tree unit size signaling may be finished.Otherwise, use_128_ctu_size_flag may be signaled. In one embodiment,use_128_ctu_size_flag may be signaled first. If use_128_ctu_size_flagmay be equal to 1, coding tree unit size signaling may be finished.Otherwise, use_32_ctu_size_flag may be signaled. In one embodiment,use_64_ctu_size_flag may be signaled first. If use_64_ctu_size_flag maybe equal to 1, coding tree unit size signaling may be finished.Otherwise, use_128_ctu_size_flag may be signaled. In one embodiment,use_128_ctu_size_flag may be signaled first. If use_128_ctu_size_flagmay be equal to 1, coding tree unit size signaling may be finished.Otherwise, use_64_ctu_size_flag may be signaled.

Referring now to FIGS. 3A-3B, according to one or more embodiments,individual flags in the sequence parameter set indicating whether thesmallest coding tree unit size may be applied(use_smallest_ctu_size_flag) and whether the largest(use_largest_ctu_size_flag) coding tree unit size may be applied. In oneembodiment, the sequence parameter set flag indicating whether thesmallest coding tree unit size may be applied may be signaled first, ifthe smallest coding tree unit size may not be applied, then anothersequence parameter set flag indicating whether the largest coding treeunit size may be applied may be signaled. In another embodiment, thesequence parameter set flag indicating whether the largest coding treeunit size may be applied may be signaled first, if the largest codingtree unit size may not be applied, then another sequence parameter setflag indicating whether the smallest coding tree unit size may beapplied may be signaled.

use_smallest_ctu_size_flag equal to 1 may specify that the luma codingtree block size of each coding tree unit may be equal to 32×32.use_smallest_ctu_size_flag equal to 0 may specify thatuse_largest_ctu_size_flag may be present.

use_largest_ctu_size_flag equal to 1 may specify that the luma codingtree block size of each coding tree unit may be equal to 128×128.use_largest_ctu_size_flag equal to 0 may specify that the luma codingtree block size of each coding tree unit may be equal to 64×64.

log 2_min_luma_coding_block_size_minus2 plus 2 may specify the minimumluma coding block size.

The variables CtbLog2SizeY, CtbSizeY, MinCbLog2SizeY, MinCbSizeY,MinTbLog2SizeY, MaxTbLog2SizeY, MinTbSizeY, MaxTbSizeY, PicWidthInCtbsY,PicHeightInCtbsY, PicSizeInCtbsY, PicWidthInMinCbsY, PicHeightInMinCbsY,PicSizeInMinCbsY, PicSizeInSamplesY, PicWidthInSamplesC andPicHeightInSamplesC may be derived as:

if ( use_smallest_ctu_size_flag ) CtbLog2SizeY = 0 elseif (use_largest_ctu_size_flag ) CtbLog2SizeY = 2 else CtbLog2SizeY = 1CtbSizeY = 1 << CtbLog2SizeY

Referring now to FIG. 3C, according to one or more embodiments,sps_max_luma_transform_size_64_flag may be signaled only if coding treeunit size may be greater than or equal to 64×64. In one embodiment, ifuse_32_ctu_size_flag may be signaled first and may be equal to 1,sps_max_luma_transform_size_64_flag may not be signaled. In oneembodiment, if use_64_ctu_size_flag may be signaled first and may beequal to 0, use_32_ctu_size_flag may be then signaled and may be equalto 1, sps_max_luma_transform_size_64_flag may not be signaled. In oneembodiment, if use_128_ctu_size_flag may be signaled first and may beequal to 0, use_32_ctu_size_flag may be then signaled and may be equalto 1, sps_max_luma_transform_size_64_flag may not be signaled.

use_32_ctu_size_flag equal to 1 may specify that the luma coding treeblock size of each coding tree unit may be equal to 32×32.use_32_ctu_size_flag equal to 0 may specify that use_128_ctu_size_flagmay be present. use_128_ctu_size_flag equal to 1 may specify that theluma coding tree block size of each coding tree unit may be equal to128×128. use_128_ctu_size_flag equal to 0 may specify that the lumacoding tree block size of each coding tree unit may be equal to 64×64.

log 2_min_luma_coding_block_size_minus2 plus 2 may specify the minimumluma coding block size.

sps_max_luma_transform_size_64_flag equal to 1 may specify that themaximum transform size in luma samples may be equal to 64.sps_max_luma_transform_size_64_flag equal to 0 may specify that themaximum transform size in luma samples may be equal to 32. When notpresent, the value of sps_max_luma_transform_size_64_flag may beinferred to be equal to 0.

The variables CtbLog2SizeY, CtbSizeY, MinCbLog2SizeY, MinCbSizeY,MinTbLog2SizeY, MaxTbLog2SizeY, MinTbSizeY, MaxTbSizeY, PicWidthInCtbsY,PicHeightInCtbsY, PicSizeInCtbsY, PicWidthInMinCbsY, PicHeightInMinCbsY,PicSizeInMinCbsY, PicSizeInSamplesY, PicWidthInSamplesC andPicHeightInSamplesC may be derived as:

if ( use_32_ctu_size_flag ) CtbLog2SizeY = 0 elseif (use_128_ctu_size_flag ) CtbLog2SizeY = 2 else CtbLog2SizeY = 1 CtbSizeY= 1 << CtbLog2SizeY

Referring now to FIG. 3D, according to one or more embodiments,sps_max_luma_transform_size_64_flag may be signaled only if coding treeunit size may not be the smallest coding tree unit size.

use_smallest_ctu_size_flag equal to 1 may specify that the luma codingtree block size of each coding tree unit may be equal to 32×32.use_smallest_ctu_size_flag equal to 0 may specify thatuse_largest_ctu_size_flag may be present.

use_largest_ctu_size_flag equal to 1 may specify that the luma codingtree block size of each coding tree unit may be equal to 128×128.use_largest_ctu_size_flag equal to 0 may specify that the luma codingtree block size of each coding tree unit may be equal to 64×64.

log 2_min_luma_coding_block_size_minus2 plus 2 may specify the minimumluma coding block size.

sps_max_luma_transform_size_64_flag equal to 1 may specify that themaximum transform size in luma samples may be equal to 64.sps_max_luma_transform_size_64_flag equal to 0 may specify that themaximum transform size in luma samples may be equal to 32. When notpresent, the value of sps_max_luma_transform_size_64_flag may beinferred to be equal to 0.

The variables CtbLog2SizeY, CtbSizeY, MinCbLog2SizeY, MinCbSizeY,MinTbLog2SizeY, MaxTbLog2SizeY, MinTbSizeY, MaxTbSizeY, PicWidthInCtbsY,PicHeightInCtbsY, PicSizeInCtbsY, PicWidthInMinCbsY, PicHeightInMinCbsY,PicSizeInMinCbsY, PicSizeInSamplesY, PicWidthInSamplesC andPicHeightInSamplesC may be derived as:

if ( use_smallest_ctu_size_flag ) CtbLog2SizeY = 0 elseif (use_largest_ctu_size_flag ) CtbLog2SizeY = 2 else CtbLog2SizeY = 1CtbSizeY = 1 << CtbLog2SizeY

Referring now to FIG. 4 , an operational flowchart illustrating thesteps of a method 400 for coding video data is depicted. In someimplementations, one or more process blocks of FIG. 4 may be performedby the computer 102 (FIG. 1 ) and the server computer 114 (FIG. 1 ). Insome implementations, one or more process blocks of FIG. 4 may beperformed by another device or a group of devices separate from orincluding the computer 102 and the server computer 114.

At 402, the method 400 includes receiving video data having a codingtree unit size.

At 404, the method 400 includes signaling the coding tree unit sizeassociated with the video data by setting two or more flags.

At 406, the method 400 includes coding the video data is based on theflags corresponding to the signaled coding tree unit size.

It may be appreciated that FIG. 4 provides only an illustration of oneimplementation and does not imply any limitations with regard to howdifferent embodiments may be implemented. Many modifications to thedepicted environments may be made based on design and implementationrequirements.

FIG. 5 is a block diagram 500 of internal and external components ofcomputers depicted in FIG. 1 in accordance with an illustrativeembodiment. It should be appreciated that FIG. 5 provides only anillustration of one implementation and does not imply any limitationswith regard to the environments in which different embodiments may beimplemented. Many modifications to the depicted environments may be madebased on design and implementation requirements.

Computer 102 (FIG. 1 ) and server computer 114 (FIG. 1 ) may includerespective sets of internal components 800A,B and external components900A,B illustrated in FIG. 4 . Each of the sets of internal components800 include one or more processors 820, one or more computer-readableRAMs 822 and one or more computer-readable ROMs 824 on one or more buses826, one or more operating systems 828, and one or morecomputer-readable tangible storage devices 830.

Processor 820 is implemented in hardware, firmware, or a combination ofhardware and software. Processor 820 is a central processing unit (CPU),a graphics processing unit (GPU), an accelerated processing unit (APU),a microprocessor, a microcontroller, a digital signal processor (DSP), afield-programmable gate array (FPGA), an application-specific integratedcircuit (ASIC), or another type of processing component. In someimplementations, processor 820 includes one or more processors capableof being programmed to perform a function. Bus 826 includes a componentthat permits communication among the internal components 800A,B.

The one or more operating systems 828, the software program 108 (FIG. 1) and the Video Coding Program 116 (FIG. 1 ) on server computer 114(FIG. 1 ) are stored on one or more of the respective computer-readabletangible storage devices 830 for execution by one or more of therespective processors 820 via one or more of the respective RAMs 822(which typically include cache memory). In the embodiment illustrated inFIG. 5 , each of the computer-readable tangible storage devices 830 is amagnetic disk storage device of an internal hard drive. Alternatively,each of the computer-readable tangible storage devices 830 is asemiconductor storage device such as ROM 824, EPROM, flash memory, anoptical disk, a magneto-optic disk, a solid state disk, a compact disc(CD), a digital versatile disc (DVD), a floppy disk, a cartridge, amagnetic tape, and/or another type of non-transitory computer-readabletangible storage device that can store a computer program and digitalinformation.

Each set of internal components 800A,B also includes a R/W drive orinterface 832 to read from and write to one or more portablecomputer-readable tangible storage devices 936 such as a CD-ROM, DVD,memory stick, magnetic tape, magnetic disk, optical disk orsemiconductor storage device. A software program, such as the softwareprogram 108 (FIG. 1 ) and the Video Coding Program 116 (FIG. 1 ) can bestored on one or more of the respective portable computer-readabletangible storage devices 936, read via the respective R/W drive orinterface 832 and loaded into the respective hard drive 830.

Each set of internal components 800A,B also includes network adapters orinterfaces 836 such as a TCP/IP adapter cards; wireless Wi-Fi interfacecards; or 3G, 4G, or 5G wireless interface cards or other wired orwireless communication links. The software program 108 (FIG. 1 ) and theVideo Coding Program 116 (FIG. 1 ) on the server computer 114 (FIG. 1 )can be downloaded to the computer 102 (FIG. 1 ) and server computer 114from an external computer via a network (for example, the Internet, alocal area network or other, wide area network) and respective networkadapters or interfaces 836. From the network adapters or interfaces 836,the software program 108 and the Video Coding Program 116 on the servercomputer 114 are loaded into the respective hard drive 830. The networkmay comprise copper wires, optical fibers, wireless transmission,routers, firewalls, switches, gateway computers and/or edge servers.

Each of the sets of external components 900A,B can include a computerdisplay monitor 920, a keyboard 930, and a computer mouse 934. Externalcomponents 900A,B can also include touch screens, virtual keyboards,touch pads, pointing devices, and other human interface devices. Each ofthe sets of internal components 800A,B also includes device drivers 840to interface to computer display monitor 920, keyboard 930 and computermouse 934. The device drivers 840, R/W drive or interface 832 andnetwork adapter or interface 836 comprise hardware and software (storedin storage device 830 and/or ROM 824).

It is understood in advance that although this disclosure includes adetailed description on cloud computing, implementation of the teachingsrecited herein are not limited to a cloud computing environment. Rather,some embodiments are capable of being implemented in conjunction withany other type of computing environment now known or later developed.

Cloud computing is a model of service delivery for enabling convenient,on-demand network access to a shared pool of configurable computingresources (e.g. networks, network bandwidth, servers, processing,memory, storage, applications, virtual machines, and services) that canbe rapidly provisioned and released with minimal management effort orinteraction with a provider of the service. This cloud model may includeat least five characteristics, at least three service models, and atleast four deployment models.

Characteristics are as follows:

On-demand self-service: a cloud consumer can unilaterally provisioncomputing capabilities, such as server time and network storage, asneeded automatically without requiring human interaction with theservice's provider.

Broad network access: capabilities are available over a network andaccessed through standard mechanisms that promote use by heterogeneousthin or thick client platforms (e.g., mobile phones, laptops, and PDAs).

Resource pooling: the provider's computing resources are pooled to servemultiple consumers using a multi-tenant model, with different physicaland virtual resources dynamically assigned and reassigned according todemand. There is a sense of location independence in that the consumergenerally has no control or knowledge over the exact location of theprovided resources but may be able to specify location at a higher levelof abstraction (e.g., country, state, or datacenter).

Rapid elasticity: capabilities can be rapidly and elasticallyprovisioned, in some cases automatically, to quickly scale out andrapidly released to quickly scale in. To the consumer, the capabilitiesavailable for provisioning often appear to be unlimited and can bepurchased in any quantity at any time.

Measured service: cloud systems automatically control and optimizeresource use by leveraging a metering capability at some level ofabstraction appropriate to the type of service (e.g., storage,processing, bandwidth, and active user accounts). Resource usage can bemonitored, controlled, and reported providing transparency for both theprovider and consumer of the utilized service.

Service Models are as follows:

Software as a Service (SaaS): the capability provided to the consumer isto use the provider's applications running on a cloud infrastructure.The applications are accessible from various client devices through athin client interface such as a web browser (e.g., web-based e-mail).The consumer does not manage or control the underlying cloudinfrastructure including network, servers, operating systems, storage,or even individual application capabilities, with the possible exceptionof limited user-specific application configuration settings.

Platform as a Service (PaaS): the capability provided to the consumer isto deploy onto the cloud infrastructure consumer-created or acquiredapplications created using programming languages and tools supported bythe provider. The consumer does not manage or control the underlyingcloud infrastructure including networks, servers, operating systems, orstorage, but has control over the deployed applications and possiblyapplication hosting environment configurations.

Infrastructure as a Service (IaaS): the capability provided to theconsumer is to provision processing, storage, networks, and otherfundamental computing resources where the consumer is able to deploy andrun arbitrary software, which can include operating systems andapplications. The consumer does not manage or control the underlyingcloud infrastructure but has control over operating systems, storage,deployed applications, and possibly limited control of select networkingcomponents (e.g., host firewalls).

Deployment Models are as follows:

Private cloud: the cloud infrastructure is operated solely for anorganization. It may be managed by the organization or a third party andmay exist on-premises or off-premises.

Community cloud: the cloud infrastructure is shared by severalorganizations and supports a specific community that has shared concerns(e.g., mission, security requirements, policy, and complianceconsiderations). It may be managed by the organizations or a third partyand may exist on-premises or off-premises.

Public cloud: the cloud infrastructure is made available to the generalpublic or a large industry group and is owned by an organization sellingcloud services.

Hybrid cloud: the cloud infrastructure is a composition of two or moreclouds (private, community, or public) that remain unique entities butare bound together by standardized or proprietary technology thatenables data and application portability (e.g., cloud bursting forload-balancing between clouds).

A cloud computing environment is service oriented with a focus onstatelessness, low coupling, modularity, and semantic interoperability.At the heart of cloud computing is an infrastructure comprising anetwork of interconnected nodes.

Referring to FIG. 6 , illustrative cloud computing environment 600 isdepicted. As shown, cloud computing environment 600 comprises one ormore cloud computing nodes 10 with which local computing devices used bycloud consumers, such as, for example, personal digital assistant (PDA)or cellular telephone 54A, desktop computer 54B, laptop computer 54C,and/or automobile computer system 54N may communicate. Cloud computingnodes 10 may communicate with one another. They may be grouped (notshown) physically or virtually, in one or more networks, such asPrivate, Community, Public, or Hybrid clouds as described hereinabove,or a combination thereof. This allows cloud computing environment 600 tooffer infrastructure, platforms and/or software as services for which acloud consumer does not need to maintain resources on a local computingdevice. It is understood that the types of computing devices 54A-N shownin FIG. 5 are intended to be illustrative only and that cloud computingnodes 10 and cloud computing environment 600 can communicate with anytype of computerized device over any type of network and/or networkaddressable connection (e.g., using a web browser).

Referring to FIG. 7 , a set of functional abstraction layers 700provided by cloud computing environment 600 (FIG. 6 ) is shown. Itshould be understood in advance that the components, layers, andfunctions shown in FIG. 7 are intended to be illustrative only andembodiments are not limited thereto. As depicted, the following layersand corresponding functions are provided:

Hardware and software layer 60 includes hardware and softwarecomponents. Examples of hardware components include: mainframes 61; RISC(Reduced Instruction Set Computer) architecture based servers 62;servers 63; blade servers 64; storage devices 65; and networks andnetworking components 66. In some embodiments, software componentsinclude network application server software 67 and database software 68.

Virtualization layer 70 provides an abstraction layer from which thefollowing examples of virtual entities may be provided: virtual servers71; virtual storage 72; virtual networks 73, including virtual privatenetworks; virtual applications and operating systems 74; and virtualclients 75.

In one example, management layer 80 may provide the functions describedbelow. Resource provisioning 81 provides dynamic procurement ofcomputing resources and other resources that are utilized to performtasks within the cloud computing environment. Metering and Pricing 82provide cost tracking as resources are utilized within the cloudcomputing environment, and billing or invoicing for consumption of theseresources. In one example, these resources may comprise applicationsoftware licenses. Security provides identity verification for cloudconsumers and tasks, as well as protection for data and other resources.User portal 83 provides access to the cloud computing environment forconsumers and system administrators. Service level management 84provides cloud computing resource allocation and management such thatrequired service levels are met. Service Level Agreement (SLA) planningand fulfillment 85 provide pre-arrangement for, and procurement of,cloud computing resources for which a future requirement is anticipatedin accordance with an SLA.

Workloads layer 90 provides examples of functionality for which thecloud computing environment may be utilized. Examples of workloads andfunctions which may be provided from this layer include: mapping andnavigation 91; software development and lifecycle management 92; virtualclassroom education delivery 93; data analytics processing 94;transaction processing 95; and Video Coding 96. Video Coding 96 may codevideo data using separate flags to replace the coding tree unit sizesyntax.

Some embodiments may relate to a system, a method, and/or a computerreadable medium at any possible technical detail level of integration.The computer readable medium may include a computer-readablenon-transitory storage medium (or media) having computer readableprogram instructions thereon for causing a processor to carry outoperations.

The computer readable storage medium can be a tangible device that canretain and store instructions for use by an instruction executiondevice. The computer readable storage medium may be, for example, but isnot limited to, an electronic storage device, a magnetic storage device,an optical storage device, an electromagnetic storage device, asemiconductor storage device, or any suitable combination of theforegoing. A non-exhaustive list of more specific examples of thecomputer readable storage medium includes the following: a portablecomputer diskette, a hard disk, a random access memory (RAM), aread-only memory (ROM), an erasable programmable read-only memory (EPROMor Flash memory), a static random access memory (SRAM), a portablecompact disc read-only memory (CD-ROM), a digital versatile disk (DVD),a memory stick, a floppy disk, a mechanically encoded device such aspunch-cards or raised structures in a groove having instructionsrecorded thereon, and any suitable combination of the foregoing. Acomputer readable storage medium, as used herein, is not to be construedas being transitory signals per se, such as radio waves or other freelypropagating electromagnetic waves, electromagnetic waves propagatingthrough a waveguide or other transmission media (e.g., light pulsespassing through a fiber-optic cable), or electrical signals transmittedthrough a wire.

Computer readable program instructions described herein can bedownloaded to respective computing/processing devices from a computerreadable storage medium or to an external computer or external storagedevice via a network, for example, the Internet, a local area network, awide area network and/or a wireless network. The network may comprisecopper transmission cables, optical transmission fibers, wirelesstransmission, routers, firewalls, switches, gateway computers and/oredge servers. A network adapter card or network interface in eachcomputing/processing device receives computer readable programinstructions from the network and forwards the computer readable programinstructions for storage in a computer readable storage medium withinthe respective computing/processing device.

Computer readable program code/instructions for carrying out operationsmay be assembler instructions, instruction-set-architecture (ISA)instructions, machine instructions, machine dependent instructions,microcode, firmware instructions, state-setting data, configuration datafor integrated circuitry, or either source code or object code writtenin any combination of one or more programming languages, including anobject oriented programming language such as Smalltalk, C++, or thelike, and procedural programming languages, such as the “C” programminglanguage or similar programming languages. The computer readable programinstructions may execute entirely on the user's computer, partly on theuser's computer, as a stand-alone software package, partly on the user'scomputer and partly on a remote computer or entirely on the remotecomputer or server. In the latter scenario, the remote computer may beconnected to the user's computer through any type of network, includinga local area network (LAN) or a wide area network (WAN), or theconnection may be made to an external computer (for example, through theInternet using an Internet Service Provider). In some embodiments,electronic circuitry including, for example, programmable logiccircuitry, field-programmable gate arrays (FPGA), or programmable logicarrays (PLA) may execute the computer readable program instructions byutilizing state information of the computer readable programinstructions to personalize the electronic circuitry, in order toperform aspects or operations.

These computer readable program instructions may be provided to aprocessor of a general purpose computer, special purpose computer, orother programmable data processing apparatus to produce a machine, suchthat the instructions, which execute via the processor of the computeror other programmable data processing apparatus, create means forimplementing the functions/acts specified in the flowchart and/or blockdiagram block or blocks. These computer readable program instructionsmay also be stored in a computer readable storage medium that can directa computer, a programmable data processing apparatus, and/or otherdevices to function in a particular manner, such that the computerreadable storage medium having instructions stored therein comprises anarticle of manufacture including instructions which implement aspects ofthe function/act specified in the flowchart and/or block diagram blockor blocks.

The computer readable program instructions may also be loaded onto acomputer, other programmable data processing apparatus, or other deviceto cause a series of operational steps to be performed on the computer,other programmable apparatus or other device to produce a computerimplemented process, such that the instructions which execute on thecomputer, other programmable apparatus, or other device implement thefunctions/acts specified in the flowchart and/or block diagram block orblocks.

The flowchart and block diagrams in the Figures illustrate thearchitecture, functionality, and operation of possible implementationsof systems, methods, and computer readable media according to variousembodiments. In this regard, each block in the flowchart or blockdiagrams may represent a module, segment, or portion of instructions,which comprises one or more executable instructions for implementing thespecified logical function(s). The method, computer system, and computerreadable medium may include additional blocks, fewer blocks, differentblocks, or differently arranged blocks than those depicted in theFigures. In some alternative implementations, the functions noted in theblocks may occur out of the order noted in the Figures. For example, twoblocks shown in succession may, in fact, be executed concurrently orsubstantially concurrently, or the blocks may sometimes be executed inthe reverse order, depending upon the functionality involved. It willalso be noted that each block of the block diagrams and/or flowchartillustration, and combinations of blocks in the block diagrams and/orflowchart illustration, can be implemented by special purposehardware-based systems that perform the specified functions or acts orcarry out combinations of special purpose hardware and computerinstructions.

It will be apparent that systems and/or methods, described herein, maybe implemented in different forms of hardware, firmware, or acombination of hardware and software. The actual specialized controlhardware or software code used to implement these systems and/or methodsis not limiting of the implementations. Thus, the operation and behaviorof the systems and/or methods were described herein without reference tospecific software code—it being understood that software and hardwaremay be designed to implement the systems and/or methods based on thedescription herein.

No element, act, or instruction used herein should be construed ascritical or essential unless explicitly described as such. Also, as usedherein, the articles “a” and “an” are intended to include one or moreitems, and may be used interchangeably with “one or more.” Furthermore,as used herein, the term “set” is intended to include one or more items(e.g., related items, unrelated items, a combination of related andunrelated items, etc.), and may be used interchangeably with “one ormore.” Where only one item is intended, the term “one” or similarlanguage is used. Also, as used herein, the terms “has,” “have,”“having,” or the like are intended to be open-ended terms. Further, thephrase “based on” is intended to mean “based, at least in part, on”unless explicitly stated otherwise.

The descriptions of the various aspects and embodiments have beenpresented for purposes of illustration, but are not intended to beexhaustive or limited to the embodiments disclosed. Even thoughcombinations of features are recited in the claims and/or disclosed inthe specification, these combinations are not intended to limit thedisclosure of possible implementations. In fact, many of these featuresmay be combined in ways not specifically recited in the claims and/ordisclosed in the specification. Although each dependent claim listedbelow may directly depend on only one claim, the disclosure of possibleimplementations includes each dependent claim in combination with everyother claim in the claim set. Many modifications and variations will beapparent to those of ordinary skill in the art without departing fromthe scope of the described embodiments. The terminology used herein waschosen to best explain the principles of the embodiments, the practicalapplication or technical improvement over technologies found in themarketplace, or to enable others of ordinary skill in the art tounderstand the embodiments disclosed herein.

What is claimed is:
 1. A method of video coding, executable by aprocessor, the method comprising: receiving video data having a codingtree unit size; and signaling, in a sequence parameter set or a sliceheader, two flags corresponding to the coding tree unit size, whereinthe signaling comprises signaling a first flag of the two flags, thefirst flag corresponding to a first coding tree unit size, and when thefirst flag is 1, coding the video data based on the first coding treeunit size without signaling a second flag of the two flags, and when thefirst flag is 0, signaling the second flag of the two flags, and codingthe video data based on the second flag that is signaled, and whereinwhen the second flag is 1, the video data is coded based on a secondcoding tree unit size, and when the second flag is 0, the video data iscoded based on a third coding tree unit size.
 2. The method of claim 1,wherein the two flags comprise two from among a 32-pixel coding treeunit size flag, a 64-pixel coding tree unit size flag, and a 128-pixelcoding tree unit size flag.
 3. The method of claim 2, wherein the32-pixel coding tree unit size flag is signaled first, and wherein the64-pixel coding tree unit size flag is signaled based on the 32-pixelcoding tree unit size flag being not equal to
 1. 4. The method of claim2, wherein the 64-pixel coding tree unit size flag is signaled first,and wherein the 32-pixel coding tree unit size flag is signaled based onthe 64-pixel coding tree unit size flag being not equal to
 1. 5. Themethod of claim 2, wherein the 32-pixel coding tree unit size flag issignaled first, and wherein the 128-pixel coding tree unit size flag issignaled based on the 32-pixel coding tree unit size flag being notequal to
 1. 6. The method of claim 2, wherein the 128-pixel coding treeunit size flag is signaled first, and wherein the 32-pixel coding treeunit size flag is signaled based on the 128-pixel coding tree unit sizeflag being not equal to
 1. 7. The method of claim 2, wherein the64-pixel coding tree unit size flag is signaled first, and wherein the128-pixel coding tree unit size flag is signaled based on the 64-pixelcoding tree unit size flag being not equal to
 1. 8. The method of claim2, wherein the 128-pixel coding tree unit size flag is signaled first,and wherein the 64-pixel coding tree unit size flag is signaled based onthe 128-pixel coding tree unit size flag being not equal to
 1. 9. Themethod of claim 2, wherein a 64-pixel max luma transform size flag issignaled based on the coding tree unit size associated with the videodata being greater than or equal to 64 pixels by 64 pixels.
 10. Themethod of claim 9, wherein based on the 32-pixel coding tree unit sizeflag being signaled first and being equal to 1, the 64-pixel max lumatransform size flag is not signaled.
 11. The method of claim 9, whereinbased on the 64-pixel coding tree unit size flag being signaled firstand being equal to 0, the 32-pixel coding tree unit size flag issignaled and set equal to 1, and the 64-pixel max luma transform sizeflag is not signaled.
 12. The method of claim 9, wherein based on the128-pixel coding tree unit size flag being signaled first and beingequal to 0, the 32-pixel coding tree unit size flag is signaled and setequal to 1, and the 64-pixel max luma transform size flag is notsignaled.
 13. The method of claim 1, wherein the first flag indicateswhether a smallest coding tree unit size is applied and the second flagindicates whether a largest coding tree unit size is applied.
 14. Themethod of claim 13, wherein the first flag is signaled first, andwherein the second flag is signaled based on the smallest coding treeunit size not being applied.
 15. The method of claim 13, wherein a64-pixel max luma transform size flag is signaled based on the smallestcoding tree unit size not being applied.
 16. The method of claim 1,wherein second flag indicates whether a smallest coding tree unit sizeis applied, and wherein the first flag indicates whether a largestcoding tree unit size is applied.
 17. A computer system for coding videodata, the computer system comprising: one or more computer-readablenon-transitory storage media configured to store computer program code;and one or more computer processors configured to access said computerprogram code and operate as instructed by said computer program code,said computer program code including: receiving code configured to causethe one or more computer processors to receive video data having acoding tree unit size; and signaling and coding code configured to causethe one or more computer processors to signal, in a sequence parameterset or a slice header, only two flags corresponding to the coding treeunit size, wherein the signaling and coding code is further configuredto cause the one or more computer processors to: signal a first flag ofthe two flags, the first flag corresponding to a first coding tree unitsize, and when the first flag is 1, code the video data based on thefirst coding tree unit size without signaling a second flag of the twoflags, and when the first flag is 0, signal the second flag of the twoflags, and code the video data based on the second flag that issignaled, and wherein when the second flag is 1, the video data is codedbased on a second coding tree unit size, and when the second flag is 0,the video data is coded based on a third coding tree unit size.
 18. Thecomputer system of claim 17, wherein the two flags comprise two fromamong a 32-pixel coding tree unit size flag, a 64-pixel coding tree unitsize flag, and a 128-pixel coding tree unit size flag.
 19. Anon-transitory computer readable medium having stored thereon a computerprogram for coding video data, the computer program configured to causeone or more computer processors to at least: receive video data having acoding tree unit size; and signal, in a sequence parameter set or aslice header, only two flags corresponding to the coding tree unit size,wherein the signaling comprises signaling a first flag of the two flags,the first flag corresponding to a first coding tree unit size, and whenthe first flag is 1, coding the video data based on the first codingtree unit size without signaling a second flag of the two flags, andwhen the first flag is 0, signaling the second flag of the two flags,and coding the video data based on the second flag that is signaled, andwherein when the second flag is 1, the video data is coded based on asecond coding tree unit size, and when the second flag is 0, the videodata is coded based on a third coding tree unit size.
 20. The computerreadable medium of claim 19, wherein the two flags comprise two fromamong a 32-pixel coding tree unit size flag, a 64-pixel coding tree unitsize flag, and a 128-pixel coding tree unit size flag.